Fasteners stamped or blanked from cold rolled steel sheets and formed into sticks or strips for continuous or magazine feeding of a plunger-type nailing machine are well known in the art. Examples of such fasteners are exemplified in U.S. Pat. Nos. 2,649,831, 2,868,057 and 2,428,259, the disclosures of which are incorporated in their entirety by reference herein. Such fasteners, more commonly termed cleats or nails, can be used to install tongue and groove wood flooring and other fibrous workpieces.
As disclosed in the foregoing patents, such fasteners are characterized by having a shank of preselected width that is substantially rectangular in cross-section. Extending perpendicularly in one direction from one end of the shank is a fastener head. The L-shaped configuration defined by the joining of the fastener head to the shank provides a surface for driving the fastener into a workpiece as well as providing the fastener with holding or fastening properties.
On an other end of these fasteners is a tapered tip for initially penetrating the workpiece. Projecting from at least one side of the shank and extending from generally an intermediate position along the shank, to nearly the tip, is a plurality of barbs, In common practice, the barbs are formed on each side of the shank in corresponding pairs.
Today, there are many tongue and groove floorings being introduced into the marketplace. Most of these new floorings are typically comprised of two or more layers and are referred to as "Engineered Flooring" or, alternatively, as "Laminate Flooring." This type of flooring can have various thicknesses of 1/2, 3/8, and 5/16 inch. For convenience this flooring shall generally be referred to herein as laminate flooring.
The tongue of laminate flooring is usually comprised of plain LUAN, cheap wood, or wood composites. These materials have very little strength for retaining a fastener.
Conventional fasteners used to install laminate flooring typically have a thickness of about 1.6 millimeters (0.062 inch). Driving these fasteners into the fragile tongue of a laminate flooring workpiece results in a high occurrence of splitting.
Moreover, driving a conventional fastener into the tongue deposits large dimples on the tongue's outer surface due to the displacement of the laminate flooring material. These dimples can inhibit or prevent the proper installation of the tongue within the groove of an adjacent laminate flooring workpiece.
Further, if the head of a conventional fastener is not properly sunk within the laminate flooring material, the fastener must be completely removed or special steps must be taken to further sink the fastener by using a punch or the like. Both of these options are time consuming and can result in damage to the flooring, especially the tongue.
Hence, prior to the present invention, a need existed for a cost-effective fastener that can be driven into a laminate flooring workpiece without causing substantial disfigurement and allowing for easy corrective measures for remedying an improperly sunk fastener.